1. Field of the Invention
The present invention relates to a disk cartridge device for recording an information signal on a signal recording layer or reproducing a recorded information signal from the signal recording layer with irradiation of optical beams on the signal recording layer of an optical disk, for example. More particularly, the present invention relates to a so-called compatible type disk cartridge device for selectively loading a plurality of disk cartridges having cartridge housings different in sizes to store disks of different diameters onto a recording and reproducing device by which disk cartridges of different sizes can be properly positioned at and held by positioning pins of the recording and reproducing device without a hitch.
2. Description of the Related Art
As media for recording a variety of information such as audio information or video information, there have hitherto been proposed optical disks for reproducing recorded information from the recording medium or recording information on the recording medium by optical beams. This kind of optical disk can be comprised of a single plate-like disk, and hence it is easy to handle. In addition, since such optical disks are large in recording capacity as compared with recording media such as magnetic tapes, they are now widely applied to recording media of audio information, video information and data processed by computers.
On the other hand, a demand of smaller recording and/or reproducing device using optical recording media such as optical disks is increasing because information processors such as computers do not have a sufficient space to incorporate recording and/or reproducing device.
Furthermore, recording media themselves have to be miniaturized and also have to increase their capacity in order to make the recording and/or reproducing device become small. To fulfill such requirements, there are proposed a plurality of types of disk cartridges including cartridge housings of different sizes to store disks of different diameters as recording media. The assignee of the present application has previously proposed these disk cartridges by as Japanese patent application No. 11-176029.
The above-mentioned disk cartridges are designed to be inserted into their own cartridge insertion slots, and hence recording and reproducing device should be designed in accordance with respective disk cartridges.
For this reason, disk cartridges, which are different in size, cannot be selectively loaded onto a compatible recording and reproducing device.
That is, the height reference position to determine the position in the height direction is not always the same in disk cartridges of different sizes. In particular, in most cases of recording and reproducing device which uses a single spindle motor, it is very difficult to make height reference planes of disk cartridges of different sizes become coincident with each other.
For example, pins of the recording and reproducing device to determine the height when they are brought in contact with the height reference plane often become obstacles against disk cartridges of different sizes in use. That is, pins to determine the height of the disk cartridge of small diameter are not required when the disk cartridge of large diameter is inserted, and hence the disk cartridge of large diameter has to escape from the pins which determine the height. Disk cartridges such as floppy disk, MD (mini disc) and MO (magnetooptical disk) are not provided with a means for avoiding such pins assumed when disk cartridges of different sizes are used by a single recording and reproducing device.
The present invention is made in order to provide a disk cartridge device by which a plurality of kinds of disk cartridges of different sizes can be located at their respective proper positions in the height direction and selectively loaded onto a single recording and reproducing device.
In order to attain the above-mentioned object, a disk cartridge device according to the present invention includes pairs of positioning pins having bases to determine the height at which disk cartridges of different sizes are respectively properly placed to a recording and reproducing device and positioning holes on one surface of disk cartridges of different sizes, the positioning holes being engaged with pairs of positioning pins and properly positioned,wherein a disk cartridge of large disk diameter includes escape holes formed on its lower surface to enable it to escape from positioning pins at which the disk cartridge of small disk diameter is properly positioned, under such loading state that the positioning holes of the disk cartridge of large disk diameter are located at said positioning pins at a proper position in the height direction.
With the above-mentioned arrangement, when the disk cartridge of large diameter is located at a proper position in the height direction and thereby loaded onto the recording and reproducing device, the disk cartridge of large diameter can escape from the positioning pins, to which the positioning holes of the small-diameter disk cartridge are fitted, by escape holes. Thus, the disk cartridges, which are different in size, can be located at their own proper positions in the height direction and thereby loaded onto the recording and reproducing device without a hitch.